Study: Alzheimer's May Be Transmissible in Rare Cases

Facts

• A new paper published Monday in Nature Medicine by a team of neurologists under the leadership of John Collinge, of the University College, London, has found that five cases of adults with early-onset dementia may be related to injections of human growth hormones.¹
• This comes as researchers examined eight people who were referred to the National Prion Clinic at the National Hospital for Neurology and Neurosurgery in London, who reportedly had all been treated with 'cadaver-derived human-growth hormone' in childhood.²
• Alzheimer's cases are either caused by rare familial genetic mutations or sporadically developed in elderly people. Yet, if these latest findings are confirmed, a third, iatrogenic — [e.g. caused by harmful complication or other ill effect by a medical activity] — form of the disease would have been discovered.¹
• According to the study, repeated exposure over multiple years to medical treatments with the hormones contaminated by both prions — proteins that can act as transmissible agents of neurodegenerative diseases — related to Creutzfeldt-Jakob disease and amyloid beta seeds could transmit Alzheimer’s disease.³
• At least 1,848 patients in the UK were treated with cadaver-derived human-growth hormone between 1959 and 1985. Since then, this medical treatment has no longer been used as experts acknowledged that some batches contaminated with an infectious protein had caused Creutzfeldt-Jakob disease in some people.⁴

Sources: ¹Economist, ²Uclh, ³CNN and ⁴BBC News.

Narratives

• Narrative A, as provided by Guardian. The findings of this study should be taken with a grain of salt. The population size was incredibly small and of the eight people researched, several were missing their genetic data. Additionally, the method of how the disease is suspected to have spread has not been implemented in nearly 40 years. While Alzheimer's being transmissible sounds scary, people need not worry.
• Narrative B, as provided by NBC. This study could have wide-reaching impacts on our understanding of Alzheimer's disease and how it should be treated in the future. Though there's no evidence that the disease can be transmitted through other medical care, the results of this study should lead to comprehensive reviews of procedures to make sure accidental transmissions like this can't happen through other surgical or medical procedures.

Predictions